链篦机-回转窑球团烟气脱硫脱硝技术研究

Study on desulfurization and denitrification technology of Chain Grate Machine——Rotary Kiln Pellet Flue Gas

本文结合球团行业的发展,重点分析了链篦机-回转窑球团脱硫脱硝现状以及存在的主要问题,并提出了非选择性催化还原脱硝+选择性催化还原脱硝和活性焦脱硫协同处理技术,以更好实现对NO、SO、粉尘及二噁英等的减排。经研究结果表明:链篦机-回转窑生产工序采用SNCR脱硝+高温SCR脱硝是治理NO超标的有效方法,而活性焦脱硫是处理后端烟气中SO的主要技术手段。同时,因活性焦特有的机理,对二噁英及重金属也有相应的脱除功能。链篦机SNCR脱硝+高温SCR脱硝后,再利用活性焦吸附特性脱硫,烟气脱硝去除率可达95%以上,而活性焦脱硫去除效率至少可达98%,且产生的SO可用于生产硫酸,具有无二次污染和资源可回收利用的优点,满足球团烟气超低排放的技术指标。

This paper combined with the development of pellet industry, mainly analyse on the current situation and existent main problems of desulfurization and denitration of grate rotary kiln pellets, and puts forward the collaborative treatment technology of non selective catalytic reduction denitration + selective catalytic reduction denitration and activated coke desulfurization, can be better realize the emission of NO, SO, dust and dioxin emission reduction. The research results show that: SNCR denitration + high temperature SCR denitration is an effective method govern NOx exceeding the standard in the production process of grate rotary kiln,while activated coke desulfurization is the main technical means to treat SOin the back-end flue gas.At the same time,because of the special mechanism of activated coke, it also has the corresponding function of removing dioxins and heavy metals.After SNCR denitration+high-temperature SCR denitration of the grate, desulfurization is carried out by using the adsorption characteristics of activated coke,the flue gas denitration removal rate can reach more than 95%, while the desulfurization removal efficiency of activated coke can reach at least 98%, moreover, the generated SOcan be used to produce sulfuric acid,it has the advantages of no secondary pollution and recyclable resources, and meets the technical index of ultra-low emission offootball team flue gas.